Physician's Weekly Article - Mapping the Way Toward Better Infection Prevention

       In 2007, the CDC updated its guidelines on isolation precautions for preventing transmission of infectious agents in healthcare settings. The guidelines broaden the key points of the 1996 recommendations, providing evidence-based strategies for infection control across all healthcare environments, including hospitals, long-term care facilities, ambulatory care, home care, and hospice. “The scope of infection-prevention extends beyond the traditional hospital setting,” says Tara MacCannell, MS, PhD. “The updated CDC guidelines recognize that infection control practices are required in other settings as well. For that reason, the expanded guidelines now include patients and healthcare personnel in all settings where healthcare is delivered.”

      The 2007 guidelines discuss in detail several infectious pathogens that have significant infection control implications; previous guidelines did not specifically discuss such pathogens at length. For example, studies on methicillin-resistant Staphylococcus aureus, or MRSA, have influenced more specific recommendations for surveillance and control measures. “In addition to the use of isolation precautions and personal protective equipment, it’s important to address the need for engineering controls,” Dr. MacCannell explains, “that either remove or prevent exposure to infectious material through technologies such as environmental ventilation. A well-recognized example of engineering controls would be the use of airborne infection isolation rooms to prevent the dissemination of tuberculosis within a facility.”

      Key Additions

      New additions to the standard precautions in the guidelines include respiratory hygiene and cough etiquette (Table 1). Dr. MacCannell says these additions were influenced by both the severe acute respiratory syndrome (SARS) outbreak that occurred in 2003 and concern that the cases of avian influenza in humans that occurred sporadically throughout the world might lead to an influenza pandemic. The new guidelines strongly recommend that healthcare personnel and patients receive education on the importance of source control measures to contain respiratory secretions. This is an important step to prevent the transmission of respiratory pathogens, especially during flu season outbreaks. The following measures are suggested:

      • Post signs at entrances and in strategic places within ambulatory and inpatient settings with instructions to individuals with respiratory infection to cover mouths/noses when coughing or sneezing, use and dispose of tissues, and perform hand hygiene.

      • Provide tissues and no-touch receptacles for disposal of tissues.

      • Provide resources and instructions for performing hand hygiene in or near waiting areas in ambulatory and inpatient settings.

      • During periods of increased prevalence of respiratory infections in the community, offer masks to coughing patients and other symptomatic persons upon entry into the facility and encourage separation (at least 3 feet) from others in common waiting areas.

      In addition to respiratory hygiene, the importance of safe injection practices is reiterated as a basic part of the standard precautions section of the guidelines. According to Dr. MacCannell, several investigations over the past 10 years have examined hepatitis B and C transmission in healthcare settings. “These studies have indicated that clinicians need to be reminded of the critical importance of safe-injection practices. In addition, the standard precautions section now endorses the use of masks during special lumbar puncture procedures, such as insertion of a catheter to inject material into the spinal canal (eg, for myelograms) and spinal or epidural anesthesia. This is to prevent bacteria from entering clinicians’ nose and mouth so that the catheter about to be inserted into the patient doesn’t accidentally become contaminated.”

      Identify Modes of Transmission

      Three specific modes of transmission (airborne, droplet, and contact) and precautions to prevent these transmissions are described in the guidelines. Transmission-based precautions with airborne diseases (eg, tuberculosis, measles, varicella, and smallpox) include placing patients in an airborne-infection isolation room and having them wear masks whenever they are outside that room; healthcare workers should wear respirators whenever entering the isolation room. For droplet precautions, patients should be placed into either single rooms or separated by a privacy curtain, and healthcare workers should wear a surgical mask and a face shield or goggles (if necessary). Examples of infections transmitted by droplet transmission (eg, coughing or sneezing) include Bordetella pertussis, influenza virus, adenovirus, rhinovirus, Mycoplasma pneumoniae, SARS, group A streptococcus, and Neisseria meningitidis.

      Contact precautions are intended to prevent transmission of infections spread by direct or indirect contact with patients or their environment. These precautions apply particularly to patients with increased potential for extensive environmental contamination (eg, uncontained wound drainage or fecal incontinence). The guideline recommends that these patients be placed in a private room, and anyone entering the room should wear isolation gowns and gloves. This equipment should be removed before leaving the patient-care area to prevent possible contamination of the environment outside the patient’s room, and should be followed by hand hygiene.

      “These CDC guidelines on isolation precautions have become a gold standard for infection prevention,” notes Dr. MacCannell. “All providers have the responsibility to engage in infection control activities. It’s critical so that clinicians can provide safer environments for patients and hopefully make healthcare-acquired infections become a thing of the past.”

      Tara MacCannell, MS, PhD has indicated to Physician’s Weekly that she has or has had no financial interests to report.